Knuckle



FIG. 1 is a front perspective view of a knuckle showing our new design;

FIG. 2 is a front elevation view of FIG. 1;

FIG. 3 is a top view of FIG. 2;

FIG. 4 is a rear perspective view of FIG. 1;

FIG. 5 is a rear elevation view of FIG. 4;

FIG. 6 is a bottom view of FIG. 5;

FIG. 7 is a right side elevation view of FIG. 2; and,

FIG. 8 is a left side elevation view of FIG. 2. 

The ornamental design for a knuckle, as shown and described. 